The invention relates to a surgical clip applicator with which generally U-shaped or V-shaped clips are typically applied to tissue structures of a patient, for example, a blood vessel, and then closed.
The surgical clip applicator comprises a handle portion, a shaft adjoining the handle portion, a clip applying tool arranged at the free end of the shaft, and a clip magazine in which a plurality of U-shaped or V-shaped clips are stored, which can be fed singly to the clip applying tool.
The applying tool comprises a mouthpiece with tool jaws for holding a clip during the application and a closing device for transferring the tool jaws from an open, idle position to a closed position in which the clips are closed and then adhere to the tissue structure or the blood vessel and occlude it.
The clip magazine is often held exchangeably on the clip applicator, as is known, for example, from DE 196 03 889 A1. A clip applicator with exchangeable clip magazine is disclosed therein. Herein the handle portion with the applicator shaft and the clip applying tool is used several times, whereas the clip magazine is used only once and is disposed of after depletion of the supply of clips. Following sterilization, the rest of the applicator can be fitted again with a fresh clip magazine and used again.
Owing to the harsh sterilization conditions, deformations may occur to some extent in clip guide tracks on which the clips are fed to the clip applying tool singly and/or in the applying tool, as a result of which, for example, clips become jammed or clips fall out of the applicator before they are fed to the applying tool. The clip applicator then has to be repaired. It is then no longer possible to put the clip magazine in use at that point in time with its supply of clips to further use.
In EP 0 793 944 B1 a clip applicator is described in which not only the clip magazine but also the mouthpiece can be exchanged as required. The problem with this applicator is that the need to exchange the mouthpiece can only be recognized by applying a clip as a test or possibly only during an operation on the patient. In such a case, the clip applicator has to be repaired, which means that the clip magazine with the remaining clips has to be discarded and the mouthpiece then exchanged, and the instrument sterilized and fitted with a new clip magazine before it can be used again.
In accordance with US 2005/0256529 A1 an applicator with a reusable handle portion and a disposable clip magazine exchangeably connectable to the handle portion is proposed, in which the steel mouthpiece is exchanged together with the clip magazine. Here the mouthpiece is exchanged each time with the used magazine, and a new mouthpiece is supplied along with each clip magazine, so that the problems occurring in usage, as described above, are prevented. However, the manufacturing costs of such disposable clip magazines with steel mouthpieces are relatively high.
A further alternative is described in U.S. Pat. No. 4,296,751, in which the complete applicator is designed as disposable article. For cost reasons it is also proposed therein that the forceps jaws of the mouthpiece be made of plastic material or plastic material reinforced with metal.
A disadvantage of this embodiment is that the plastic material, even when reinforced with plastic, does not produce satisfactory results when closing the clips, as the closing forces to be applied can only be transmitted to an insufficient extent by the plastic forceps jaws. Double-shank or multiple clips cannot be used with such applicators as the necessary closing forces cannot be transmitted here.
The object of the present invention is to propose a clip applicator, which, on the one hand, can be manufactured economically and, on the other hand, allows secure closure of the clips when applied to tissue structures, in particular, also in the case of double-shank or multiple clips.